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Overlaying histograms with ggplot2 in R
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Your current code:
ggplot(histogram, aes(f0, fill = utt)) + geom_histogram(alpha = 0.2)
is telling ggplot to construct one histogram using all the values in f0 and then color the bars of this single histogram according to the variable utt.
What you want instead is...
Does Ruby regular expression have a not match operator like “!~” in Perl?
... from the documentation page of Regexp. Nevertheless, it works:
irb(main):001:0> 'x' !~ /x/
=> false
irb(main):002:0> 'x' !~ /y/
=> true
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How can I extract a good quality JPEG image from a video file with ffmpeg?
...2).
To output a series of images:
ffmpeg -i input.mp4 -qscale:v 2 output_%03d.jpg
See the image muxer documentation for more options involving image outputs.
To output a single image at ~60 seconds duration:
ffmpeg -ss 60 -i input.mp4 -qscale:v 4 -frames:v 1 output.jpg
This will work with any vid...
Counting inversions in an array
...on in java.
long merge(int[] arr, int[] left, int[] right) {
int i = 0, j = 0, count = 0;
while (i < left.length || j < right.length) {
if (i == left.length) {
arr[i+j] = right[j];
j++;
} else if (j == right.length) {
arr[i+j] = lef...
SQL how to increase or decrease one for a int column in one command
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answered Jun 10 '09 at 2:01
gahooagahooa
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How to limit UITableView row reordering to a section
...ath.section != proposedDestinationIndexPath.section) {
NSInteger row = 0;
if (sourceIndexPath.section < proposedDestinationIndexPath.section) {
row = [tableView numberOfRowsInSection:sourceIndexPath.section] - 1;
}
return [NSIndexPath indexPathForRow:row inSection:sourceInde...
Relative frequencies / proportions with dplyr
...n = n()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
From the dplyr vignette:
When you group by multiple variables, each summary peels off one level of the grouping. That makes ...
Error: Could not create the Java Virtual Machine Mac OSX Mavericks
I just installed the latest Java SDK 7-67 from Oracle on the Mac 10.9.4. I then ran the command java -v in Terminal and I get this message:
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WAMP/XAMPP is responding very slow over localhost
... performance:
Change apache's listening port
Change listening port from 80 to 8080 to avoid conflicts with programs like Skype. Open your httpd.conf file and find the line that starts with Listen (it's around line 62). Change it like the following:
Listen 127.0.0.1:8080
Change your powerplan
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How to get 0-padded binary representation of an integer in java?
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201
I think this is a suboptimal solution, but you could do
String.format("%16s", Integer.toBinary...